One of the differences between the cell membrane and the cell wall is in the type of organisms that they are found in. A cell wall is found in plants only. A cell membrane is found in all organisms including plants. Present only in plants, and in some fungi, bacteria, algae.
Cutting down trees results in loss of habitat for many animals in the wild, because over 70% of animals that live on land live in trees! Cutting down trees can also reduce our oxygen.
Cause it does not have to be followed by and believed by the theory itself.